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        <h2>
          <span class="refentrytitle">gain</span>
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        <p>gain — 
      Adjusts the amplitude audio signal according to a root-mean-square value.
    </p>
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      <div class="refsect1">
        <a id="idp112143552"></a>
        <h2>Description</h2>
        <p>
      Adjusts the amplitude audio signal according to a root-mean-square value.
    </p>
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      <div class="refsect1">
        <a id="idp112205648"></a>
        <h2>Syntax</h2>
        <pre class="synopsis">ares <span class="command"><strong>gain</strong></span> asig, krms [, ihp] [, iskip]</pre>
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      <div class="refsect1">
        <a id="idp112207840"></a>
        <h2>Initialization</h2>
        <p>
      <span class="emphasis"><em>ihp</em></span> (optional, default=10) -- half-power point (in Hz) of a special internal low-pass filter. The default value is 10.
    </p>
        <p>
      <span class="emphasis"><em>iskip</em></span> (optional, default=0) -- initial disposition of internal data space (see <a class="link" href="reson.html" title="reson"><em class="citetitle">reson</em></a>). The default value is 0.
    </p>
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      <div class="refsect1">
        <a id="idp112211424"></a>
        <h2>Performance</h2>
        <p>
      <span class="emphasis"><em>asig</em></span> -- input audio signal
    </p>
        <p>
      <span class="emphasis"><em>gain</em></span> provides an amplitude modification of <span class="emphasis"><em>asig</em></span> so that the output <span class="emphasis"><em>ares</em></span> has rms power equal to <span class="emphasis"><em>krms</em></span>. <a class="link" href="rms.html" title="rms"><em class="citetitle">rms</em></a> and <span class="emphasis"><em>gain</em></span> used together (and given matching <span class="emphasis"><em>ihp</em></span> values) will provide the same effect as <a class="link" href="balance.html" title="balance"><em class="citetitle">balance</em></a>.
    </p>
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      <div class="refsect1">
        <a id="idp112217952"></a>
        <h2>Examples</h2>
        <p>
      Here is an example of the gain opcode. It uses the file <a class="ulink" href="examples/gain.csd" target="_top"><em class="citetitle">gain.csd</em></a>.

      </p>
        <div class="example">
          <a id="idp112219808"></a>
          <p class="title">
            <strong>Example 340. Example of the gain opcode.</strong>
          </p>
          <div class="example-contents">
            <p>See the sections <a class="link" href="UsingRealTime.html" title="Real-Time Audio"><em class="citetitle">Real-time Audio</em></a> and <a class="link" href="CommandFlags.html" title="Csound command line"><em class="citetitle">Command Line Flags</em></a> for more information on using command line flags.</p>
            <pre class="programlisting">
<span class="csdtag">&lt;CsoundSynthesizer&gt;</span>
<span class="csdtag">&lt;CsOptions&gt;</span>
<span class="comment">; Select audio/midi flags here according to platform</span>
-odac     <span class="comment">;;;realtime audio out</span>
<span class="comment">;-iadc    ;;;uncomment -iadc if realtime audio input is needed too</span>
<span class="comment">; For Non-realtime ouput leave only the line below:</span>
<span class="comment">; -o gain.wav -W ;;; for file output any platform</span>
<span class="csdtag">&lt;/CsOptions&gt;</span>
<span class="csdtag">&lt;CsInstruments&gt;</span>

<span class="ohdr">sr</span> <span class="op">=</span> 44100
<span class="ohdr">ksmps</span> <span class="op">=</span> 32
<span class="ohdr">nchnls</span> <span class="op">=</span> 2
<span class="ohdr">0dbfs</span>  <span class="op">=</span> 1

<span class="oblock">instr</span> 1

  asrc <span class="opc">buzz</span>  .8, 440, <span class="ohdr">sr</span><span class="op">/</span>440, 1    <span class="comment">; band-limited pulse train.</span>
  a1   <span class="opc">reson</span> asrc, 1000, 100       <span class="comment">; Sent through</span>
  a2   <span class="opc">reson</span> a1, 3000, 500         <span class="comment">; 2 filters</span>
  krms <span class="opc">rms</span>   asrc                  <span class="comment">; then balanced</span>
  afin <span class="opc">gain</span>  a2, krms              <span class="comment">; with source</span>
       <span class="opc">outs</span>  afin, afin
<span class="oblock">endin</span>


<span class="csdtag">&lt;/CsInstruments&gt;</span>
<span class="csdtag">&lt;CsScore&gt;</span>
<span class="comment">;sine wave.</span>
<span class="stamnt">f</span> 1 0 16384 10 1

<span class="stamnt">i</span> 1 0 2
<span class="stamnt">e</span>
<span class="csdtag">&lt;/CsScore&gt;</span>
<span class="csdtag">&lt;/CsoundSynthesizer&gt;</span>
</pre>
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        <p><br class="example-break" />
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        <a id="idp112224096"></a>
        <h2>See Also</h2>
        <p>
      <a class="link" href="balance.html" title="balance"><em class="citetitle">balance</em></a>,
      <a class="link" href="rms.html" title="rms"><em class="citetitle">rms</em></a>
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